Centralized computer systems with multiple computer terminals for accessing the centralized computer systems were once the dominant computer architecture. Mainframe computer systems were shared by multiple computer users in a manner wherein each individual computer user had access to a separate computer terminal system coupled to the mainframe computer system.
In the late 1970s and early 1980s, personal computer systems revolutionized the computing industry by allowing each individual user to have access to their own full computer system. Each computer user could run their own software applications on their own personal computer system and did not need to share any of the personal computer's resources with any other computer user.
Although personal computers have become the dominant form of computing, there has been a resurgence of the centralized computer system with multiple terminals form of computing. Terminal based computer systems can have reduced maintenance costs since the individual computer users cannot easily introduce computer viruses into the computer system or load in unauthorized software programs that may cause problems for the computer system. Furthermore, modern personal computer systems have become so powerful that their computing resources generally sit idle for the vast majority of the time such that valuable computing resources are being used very inefficiently.